Read the following announcement and mark the letter A, B, C, or D on your answer sheet to indicate the correct option that best fits each of the numbered blanks from 13 to 16

IMPORTANT RULES FOR BUS TRAVELERS
1. Make sure you have your ticket ready before ___(1)___ the bus.
2. Seats near the front are reserved for ___(2)___ passengers, including the elderly and those with disabilities.
3. ___(3)___ to any instructions from the driver or conductor to ensure safety during your journey.
4. Do not block the doors or emergency exits in case of ___(4)___.